Suction electrode



.I am.V 1, 1952, w. w. WELSH sucTIoN ELECTRODE Filed .my 12, 195o MWWeb/L Patented Jan. 1, 1952 SUCTION ELECTRODE Wiuiam W. Welsh,Rockville, Ma.,` assigner to. Bowen &.C'ompany, Inci, Bethesda, Md.a;co1'- poration of Delaware Application July 12, 1950, Serial No. 173,348

trically connected to the skin of a patient for electrocardiographicand' similar purposes.

In` general the device comprises a` terminal clamp to be connected inthe circuit or circuits of an electrocardiograph machine, said terminalclamp being in electrical connection with a con-f ductive cup memberadapted' to contact the skin ofthe patient. Suitable means areprovidedfor at least partially evacuating the cup member to createsufficient suction to establish good electrical contact between the cupmember and the skin of`a'patient and' to holdV the device in place. `Itis therefore an object of this invention to provide a suction electrodethat may be readily and easily applied to theskn of' the patient;

It is a further obiect of this invention to provide a suction electrodecapable of.' establishing iirml contactfwith the skin of a patientwithout the necessity of employing straps or clamps.

It is a further object oi"A thisinvention to provide a suctionelectrodel that may be `applied to the skin of a patientby a simplemanipulation of the device involving only the use of onehand.

It is another obiect of this invention to provide` a suction electrodeof unique design. and

` simple and.' economical construction.

Further objects: and advantages will appearzas the'ldescriptionproceed's in connection.` with the accompanying drawings`Vwherein:

Fig. 1` isV avertical sectional view of oneem bodiment of the v presentinvention..

Fig. 2 is a verticalsectionalviewfof4 a different embodiment or theinvention, and

Fig; 3 i w a vertical sectionalview of. a still iurther modic'ation.

The modification shown in'` Fig. l comprises a generallv hemispbericalcup member 2 having lan unwardlv extending hollow boss 3': integraltherewith. The boss 3isprovidedwithlaperiph'- eral ringer-engaging ange`4 about its upper end. Preferably. the cu'o member 2" will be made of'asuitable electrically conductive metal and a terminal clamp 5 is rigidlyattached to` the cup member ,2' in. any suitable manner, such as byriveting `a portion 6 thereof in a countersunk opening through thecupmember 2, or by soldering, welding. or the like. The terminal clamp 5may be provided with atransverse `opening 1 and a clamp screw 8 tosuitably connectvthe terminal end of a circuit conductor to the cup 2..Adjacent the mouth oi" the cup member 2is an inwardly facing-peripheralrecess or groove 9 spaced slightlyl inwardly ofther peripheral edge II)which Vdefines the mouth-ofthe cup member 2. A' exible ri-lijzpl'lragmAI I ofrubber`v` or-the like is provided with arolledioninturnedfedge I-2 Vembracing aring I3; The ring I31ispreferably asplit ring ofresilientmaterial whereby it may be positioned` in the recess 9 to clamp theperipheraledgeof` the diaphragmV II to tlxeAcupnu-imber` 2 with anair-tight seal, thus clening1 a flexible partition slightly inwardly ofthe mouth of the cup member. 2.

Anintegral boss I4 on the diaphragm. ILI extends inwardly of thecupmember 2 and has attached thereto, byrmeans of pin I5 a suitableactuating plunger I6. The lower endof plunger I6 may; as shown, beembedded in the material oi the boss |41. The plunger I 6` extendsupwardly through an enlarged opening IIv providing communication betweenthe interior of the cup member 2 and the interior of the hollow boss 3.The member IE extends outwardly through the hollowV boss 3 and isyattached at its outer end to a hollow cap` I8. The cap I8 extends intoand is guided by the hollow interior of the boss 3 and houses a suitablecompression spring I9. The compression spring I9 abuts at one endagainst the bottom of the hollow interior of the boss 3 and at its upperend abuts the interior of the cap I8;

In the'position shown in Fig. 1, the spring I9` is under compression andnormally tends to` urge the cap I8, plunger I6. and boss I4 upwardly todraw the diaphragm II- upwardly into the cup member 2.

Inuse the device of Fig; l` will rst be suitably connected to aconductor, by means of terminal clamp 5, and the cap I8 will bedepressed to the position shown in Fie. 1 before applicationto theskinof ak patient. With the partsV in the position shown in Fig. 1, theelectrode is positioned against the` patients skin at' the i desired'position with theperipheral edge IIIof the mouth` of the cup member insnug contact with thepatients skin. After; such contact ismade, canmember I8 may be released whereupon spring I9 will expand and draw thediaphragm H upwardly into the cup memberA 2, thus creating a partialvacuum between the diaphragm I I4 andthe patients skin. Thepartialvacuum thus created will result in the cup member Zbeing rmly held, byatmospl'ierc pressure,` against the skin of the patient, thusestablishing good electrical contact therewith. To release theelectrode, itis only necessaryto-.depressthecap I8to the position-ofFig. 1, whereupon the pressure betweenthe diaphragm I'I and lthepatientsskin will again be raised-'to substantially atmospheric pressureand the device may readily-be lifted from the patient.

Referring new7 to Fig. 2, the embodiment shown therein comprises agenerally cylindrical cup memberin'havinga free peripheral` edge 2lidefining the open mouth thereof; The cup member 2D' wiilalso be made of`suitable` electrical-ly conductive'` material i and f-isprovided" with ahollow; upstanding, integrai bossl 22f havingV a O-ring 28 of rubber orthe like.

.connection with Eig. 2.

3 linger-engaging ange 23 thereon. An opening 24 establishescommunication between the interior of the hollow boss 22 and theinterior of the cup member 20. A piston 25 having a piston rod 26 ispositioned within the cup member 2U with the rod 26V extending throughopening 24 into and through the hollow interiorrof the boss 22. Thepiston 25 is provided with a suitable peripheral groove 21 receiving asuitable The normal outer diameter of the O-ring 28 is slightly greaterthan the internal diameter` of the cup member 20 whereby the ring 28 isheld in radial compression when assembled in the manner shown in Fig. 2.The ring 28 provides an airtight seal between the piston 25and thecylinrdrical cup'20.

A cap member 29 is threadedly connected to the rod 26 and is of suchdiameter and length as to be readily received in and guided by thehollow interior of the boss 22 whereby movement of the cap member 29downwardly results in driving the piston 25 downwardly within the cupmember 20.V A suitable compression spring 30 is housed within the hollowboss 22 and abuts at one end against the partition wall between the boss22 and the cup member 25 and at its other end abuts a downwardly facingshoulder defined by the lowermost end of the cap 29. The compressionspring 30 normally tends to assume the position shown in Fig. 2 so thatdepression of the cap 29 will compress the spring 3|). The spring 30therebyl normally urges piston 25 upwardly to the position shown in Fig.2.

A clamp member 3| of suitable electrically conductive material is firmlyconnected to the boss 22 to establish electrical contact therewith andmay be provided with a split portionv 32 and clamp screw 33 whereby anelectrical conductor may be clamped thereto in rm electrical contact.Thus the member 3| provides for establishing electrical contact betweenan external circuit and the conductive cup member 20.

The operation of the embodiment just described in connection with Fig. 2is identical with the operation described in connection with theembodiment of Fig. 1, that is, after connection to the circuit of anelectrocardiograph or other machine, the cap 29 and piston 25 may bedepressed, the device may then be placed against the skin of a patient,and upon release of cap 29, spring 30 will move the piston 25 upwardly,thus creating a partial vacuum between the piston 25 and the skin of thepatient to utilize atmospheric pressure to hold the peripheral edge 2|of the cup 23 in firm electrical contact with the patient. v

The embodiment shown in Fig. 3 comprises a substantially hemisphericalcup 35 of conductive material having a peripheral edge 36 defining theopen mouth of the cut. A metallic tubular connector 31 having a reducedend portion 38 is attached to the cup member 35 with the reduced endportion 38 extending through an opening in the cup member. The ntbetween the reduced end portion 38 and the cup 35 may be a tightirictional t or the reduced end portion may be expanded after assemblyor may be Y soldered or otherwise fastened to the cup member to form apermanent assembly establishing good electrical contact at the joint.

A conductor clamping member 39 surrounds the tubular member 31 and maybe substantially identical to the clamp member 3| described'in The clampmember 39 will, however, be in rm electrically conductive contact withthe tubular member 31.

A resilient hollow bulb 48 of vrubber or like material has an extendingneck portion 4| tightly embracing the tubular member 31 outwardly of theterminal clamp 39. The tubular member 31 Vthus establishes communicationbetween the interior of the flexible bulb 4U and the interior of the cupmember 35.

The exible bulb 40 is suiciently rigid to normally assume the positionshown in Fig. 3 with the generally spherical bulb portion fullyextended. In applying the device of Fig. 3, the terminal end of thedesired conductor will first be clamped in the clamp member 3S and theoperator will then squeeze the bulb 40 to collapse the same, thusexpelling a substantial portion of the air therein through the tubularmember 31 and outwardly of the cup member 35. While the bulb ismaintained in such collapsed condition, the cup member 35 is engagedwith the skin of the patient by rmly pressing the peripheral edge 36against the patients skin. While being so held, the bulb 40 is releasedand will expand to the position of Fig. 3 due to its own resiliency,thus creating a partial vacuum Within the cup member 35 and againutilizing atmospheric pressure to maintain the cup member 35 in rmelectrical contact with the patient. To release the device it isnecessary only to squeeze the bulb 4D to collapse the same, whereuponlthe entire electrode may be readily lifted from the patient.

While a limited number of specific embodiments of the invention havebeen shown and described herein, it is to be understood that theinvention is not limited thereto but encompasses all modificationsfalling fairly within the scope of the appended claim.

I claim:

A suction electrode comprising, a cup member of electrically conductivematerial, said cup member being in the shape of a spherical segment nogreater than a hemisphere and having a smooth terminal edge defining anopen mouth, a tubular member of electrically conductive material iixedto said cup member and extending therefrom in a direction away from saidopen mouth, the interior of said tubular member communicating with theinterior of said cup member, a terminal clamp xed to said tubularmember, and a hollow resilient bulb having a short integral neck portionembracing said tubular member with the interiors thereof incommunication whereby to provide an air passageway between the interiorsof said bulb and cup member,said terminal clamp being provided with anopening through which said tubular member extends with a tight iit andbeing closely adjacent said cup member, said neck portion of said bulbabutting said terminal clamp whereby to maintain the overall'length ofsaid electrode at a minimum.

WILLIAM W. WELSH.

. REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Y Name Date 158,224 Stephens Dec. 29, 1874655,747 Winckeld Aug. 14, 1900 839,649 Roth Dec. 25, 1906 1,585,104Montgomery Ma;r 18, 19,2()`

